Gas mixer



M. E.WARD

April 20, 1954 GAS MIXER Filed April 18 1951 INVENTOR. Mark fhbra w yw/Patented Apr. 20, 1954 UNITED TE Ton-"Iss Mark E. Ward, Columbus, .Qhio, assign: to Surface Combustion Corporation, Toledo, Ohio, a

corporation of- Ohio Application Ap'niis, 1951, Serial No.221,643

This invention relates to gas mixers of the type where a jet of fuel gasfrom a nozzle is directed into the mouth of a mixing tube in a manner toentrain primary air, mixers of this type being commonly employed withgas burners.

It is well known that air in a dwelling contains lint and that in courseof time this lint tends to clog an ordinary air shutter for a gas mixersuch as for example a rotary type of air shutter. The object of thepresent invention is to provide an air shutter of a type that lint inthe air cannot readily clog.

For a consideration of what I consider to be novel and my invention,attention is directed to the following specification and the concludingclaims thereof.

In the accompanying drawing this specification- Fig. 1 is a sideelevation with parts in section of apparatus embodying the presentinvention.

Fig. 2 is a sectional view on line 2-2 of Fig. 1.

Fig. 3 illustrates a modified form of the invention.

Fig. 4 is a sectional view on line 4-4 of Fig. 3.

Fig. 5 illustrates another modified form of the invention.

Fig. 6 is a sectional view on line 6-6 of Fig. 5.

The apparatus with which the present invention has special utilitycomprises a mixing tube generally indicated at In, the same beingslidably supported in a conduit I l leading to a burner l2, the conduitbeing shown as supported on a bracket l3 on a base member H. The throatof the mixforming part of 2 Claims. (01. 158,-118) ing tube is indicatedat IS, the same having a For reasons presently appearing, the externaldiameter of the hollow head I9 is such that a substantial portion of itslength from the leading face 22 of the end wall I8 is adapted to betelescopically received, like a piston, by the leading end of the throatl5, the range of axial adjustment of said tube It! being such that itmay be backed away from the leading peripheral edge of said face 22 toprovide an air gap of substantial size for the admission of a relativelylarge quantity of air to the mixing tube depending on the kind of fuelbeing used. On the other hand, where the quantity of air required to beadmitted to said throat is so small that the leading peripheral edge ofsaid face 22' and .of said throat would have'to .be objectionablyclosetogether from the standpoint of linting, the present invention, as willpresently appear, provides a relatively unrestricted air-inlet portwhose effective size may be readily adjusted by varying the distance towhich the leading edge of said face 22 extends into said throat I5.

In the form of the invention shown in Fig. 1, the said relativelyunrestricted air-inlet port for relatively small quantities of air isgenerally indicated at 23, the same being formed by a notched orslanting portion 24 on the leading face 22 of said end wall 18 in adirection away from said throat, the slant being shown as beginning at aline or chord below the nozzle ll. It will be readily appreciated thatthe effective size of said port 23 can be varied as desired by varyingthe degree to which the leading peripheral edge of said face 22 extendsinto said throat [5.

In the form of the invention shown in Fig. 3, the leading face of thefront end wall I8 of the head I9 is identified by reference numeral 25,the entire surface of said face 2 5 being in a common plane incontra-distinction to the face 22 in Fig. 1 which has the slantingportion 24. In Fig. 3, the side wall of the front portion of the throatI 5 is provided with a triangular or V-shape aperture 26 whose apex isdown stream from the leading edge of said throat. When the leadingperipheral edge of said face 25 is telescopically received by theleading edge or end of the throat l5, said aperture serves as arelatively unrestricted port for the admission of air to the mixing tubeand since the tube is axially adjustable relative to said face 25, theeffective size of said port may be varied as desired as will now bereadily understood.

In the form of the invention shown in Fig. 5, the air shutter comprisesa cylindrical flange 21 on the hollow head 28 to which the gas supply 20delivers and from the front end of which the nozzle l1 extends, thediameter of said flange being such that it may be telescopicallyreceived, like a piston, by the leading end of said throat l5. Theleading face 29 of the flange is in a plane which is inclined tothe axisof said throat, the entire face of said flange being in said plane.Since the throat I5 is adjustable axially relative to said flange, byvarying the degree to which the flange 21 extends within said throat itfollows that the effective size of air inlet port between the trailingedge 30 of the face 20 of said flange 29 and the leading end or edge 3|of said throat may be varied as desired.

From the foregoing description, it is believed to be apparent that thepresent invention provides an air shutter which is well adapted for itsintended purpose.

What I claim as new is:

1. In gas mixers formed by a nozzle for discharge of gas into a conduitand an axially movable mixing tube forming part of said conduit andadapted to move toward saidnozzle to constitute an air passage betweenthe leading outer edges of said nozzle and tube as the tube moves towardthe nozzle, the improvement wherein said leading outer edge of saidnozzle is notched to form a wider and relatively unrestricted airpassage into the conduit at one point around the periphery of saidleading edge as said tube is moved toward said nozzle.

2. In gas mixers formed by members comprising a nozzle for discharge ofgas into a conduit and an axially movable mixing tube forming part ofsaid conduit and having a flared mouth, and forming in a closed positiona contact area between the nozzle and the tube, a substantial portion ofsaid contact area of one of said members removed to form a wider,relatively unrestricted air passage into the conduit at one portion ofsaid contact area.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 422,299 Danforth etal Feb. 25, 1890 1,013,000 Dowins Dec. 26,1911 1,249,382 Hale Dec. 11, 1917 1,252,707 Lewis Jan. 8, 1918 1,286,493Bailey Dec. 3, 1918 1,316,682 Calef Sept. 23, 1919 1,411,063 NeedhamMar. 28, 1922 2,269,333 Bloom Jan. 6, 1942 FOREIGN PATENTS NumberCountry Date 252,448 Great Britain May 25, 1926

